package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.sky.constant.MessageConstant;
import com.sky.dto.UserLoginDTO;
import com.sky.entity.User;
import com.sky.exception.LoginFailedException;
import com.sky.mapper.UserMapper;
import com.sky.properties.WeChatProperties;
import com.sky.service.UserService;
import com.sky.utils.HttpClientUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;

/**
 * @author Encounter
 * @date 2024/09/14 13:31<br/>
 */
@Service
public class UserServiceImpl implements UserService
    {
        private static final String WX_LOGIN = "https://api.weixin.qq.com/sns/jscode2session";
        
        @Autowired
        private WeChatProperties weChatProperties;
        
        @Autowired
        private UserMapper userMapper;
        
        /**
         * wx 登录
         *
         * @param userLoginDTO 用户登录 DTO
         * @return {@link User 用户信息}
         */
        @Override
        public User wxLogin(UserLoginDTO userLoginDTO)
            {
                //调用微信接口服务，获得当前微信用户的openid
                String openid = getOpenId(userLoginDTO.getCode());
                
                //判断openid是否为空，若为空则表示登录失败，抛出业务异常
                if (openid == null)
                    throw new LoginFailedException(MessageConstant.LOGIN_FAILED);
                
                //判断当前用户是否为新用户
                User user = userMapper.getByOpenId(openid);
                
                //如果是新用户，自动完成注册
                if (user == null)
                    {
                        user = User.builder()
                                .openid(openid)
                                .createTime(LocalDateTime.now())
                                .build();
                        userMapper.insert(user);
                    }
                
                //返回这个用户对象
                return user;
            }
        
        /**
         * 调用微信接口服务，获得当前微信用户的openid
         *
         * @param code 登录码
         * @return {@link String openid}
         */
        private String getOpenId(String code)
            {
                Map<String, String> map = new HashMap<>();
                map.put("appid", weChatProperties.getAppid());
                map.put("secret", weChatProperties.getSecret());
                map.put("js_code", code);
                map.put("grant_type", "authorization_code");
                String json = HttpClientUtil.doGet(WX_LOGIN, map);
                
                JSONObject jsonObject = JSON.parseObject(json);
                return jsonObject.getString("openid");
            }
    }
